package com.picperweek.common4android.util;

/**
 * 坐标工具类
 * @author widebluesky
 *
 */
public class LocationUtil {
	private static final double EARTH_RADIUS = 6378137.0;

	// public static void main(String[] args) {
	// double lo1 = 108.90, la1 = 34.1;// 第一个经纬度
	// double lo2 = 115.4648060, la2 = 38.8738910;// 第二个经纬度
	// System.out.println("经纬度结果:" + getDistance(lo1, la1, lo2, la2));
	// System.out.println("经纬度结果:" + getDistance(0, 0, 0, 0));
	//
	// }

	/**
	 * 获取两经纬度坐标距离
	 * @param longitude1
	 * @param latitude1
	 * @param longitude2
	 * @param latitude2
	 * @return
	 */
	public static double getDistance(double longitude1, double latitude1, double longitude2, double latitude2) {
		double Lat1 = rad(latitude1);
		double Lat2 = rad(latitude2);
		double a = Lat1 - Lat2;
		double b = rad(longitude1) - rad(longitude2);
		double s = 2 * Math.asin(Math
				.sqrt(Math.pow(Math.sin(a / 2), 2) + Math.cos(Lat1) * Math.cos(Lat2) * Math.pow(Math.sin(b / 2), 2)));
		s = s * EARTH_RADIUS;
		s = Math.round(s * 10000) / 10000;
		return s;
	}

	private static double rad(double d) {
		return d * Math.PI / 180.0;
	}
}
